More on WhatsApp

EU member states' competition authorities have been notified of Facebook's request, the WSJ said, which may be an effort by the social networking company to head off separate competition reviews in individual European countries.

Despite pressure from telcos over the acquisition, due to the dominant position it would give Facebook in messaging and the threat it poses to their SMS revenues, it's not certain whether Facebook's request will lead to a full review, the WSJ said. A Europe-wide probe would only come into effect if three countries' regulators decided it warrants a local review.

Facebook and the EC Competition Commission declined to comment on the report.

Announced in February, the $19bn deal is Facebook's biggest acquisition to date and the largest of any tech startup in recent times. Facebook is pitching the takeover as a way to build out its own chat and messaging features.

However, despite likely integration between WhatsApp and Facebook's services, the company has said it intends to run WhatsApp as an independent business.